Board handling device for a multistage hot plate press



A pril1 l969 'm'wRu JIINNOI 3,435,966

BOARD HANDLING DEVICE FOR A MULI'ISTAGE HOT PLATE PRESS" I Filed Jan. 11. 19 8 'INVENTOIR."

United States Patent US. Cl. 21416.6 Claims ABSTRACT OF THE DISCLOSURE In an attempt of obtaining a pusher rod adapted to push the material to be treated on each hot plate of a multistage hot plate press or to unload hot pressed boards out of the hot plate of the press along a straight line which is parallel to the center line i.e., the longitudinal or transverse axis of the hot press while reducing the space in which the pusher and swings from the retracted to the extended position, a connecting rod, which is maintained in balance by means of a pair of tension members, such as sprocket chains, working in opposite direction to each other, is provided between the pusher rod and a horizontally revolving arm. One end of this connecting rod is hinged on the horizontally revolving arm at the free end thereof, and the other end is adjustably connected to the inner end of pusher rod. By action of the pair of tension members such as sprocket chains, each pivoted on the connecting rod, the outer end of the pusher rod is forced to move along a modified involute curve thereby being maintained nearly along a straight line convenient for loading of material into the hot-plate press or unloading of hot-pressed boards out of the press after the tip of the pusher rod having been brought into contact with the material to be treated or the pressed boards.

The present invention relates to a hot-pressed board handling device for a multistage hot plate press, more particularly to a handling device adapted to displace hot-pressed boards, such as plywood or veneer, or the material to be treated, for a predetermined distance so as to feed the material to the hot plate or to transfer the pressed boards to the clamping means of the unloading mechanism upon completion of the hot pressing operation.

In the prior art, a number of devices have been known for the purpose. For instance, there have been developed a hot-pressed material handling device comprising a set of pusher rods adapted to move only linearaly from the loading end of the hot press, a device comprising a pusher rod adapted to pivot about a fixed point, etc., each intended for extracting the hot plates from the hot press. However, the above-mentioned first device is disadvantageous in that it becomes bulky although it is ideal in that it displaces the hot-pressed plate exactly along a straight line. The second device is also disadvantageous in that it tends to displace the hot-pressed boards out of the straight line, since the hot-pressed boards are moved by a pivoting motion of the pusher rods, and tends to occupy a substantial area. The device according to this invention has been devised to overcome the above-mentioned disadvantages.

In the present invention, it is contemplated to furnish a board handling device similar to the work impelling unit disclosed in US. Patent No. 2,989,774 issued on June 27, 1961 to Harold E. Erickson et al.

It is an object of the present invention to provide a hotpressed-boards or material to be hot-pressed handling device (will be referred to as a board-handling device 3,435,966 Patented Apr. 1, 1969 ice hereinafter) comprising a pusher rod requiring a minimum space in which it is operated and Which is substantially reduced by means of a special link mechanism and yet assuring substantially a linear displacement of the hot pressed boards or the like.

It is another object of the present invention to provide a board handling device which is simple to construct, readily arranged onto the hot press and easy to operate.

According to the present invention, there is provided a board handling device for a multistage hot-plate press comprising, at least one rotating shaft located on one side of said hot plate press at loading end thereof, a revolving arm fixedly mounted on said shaft so as to rotate together with the same, a means for connecting a pusher rod to said revolving arm, a cam ring mounted on said shaft rotatably with reference to the latter but nonrotatably secured onto a structure of said hot pressing oven, at first tension member such as a chain trained over said can ring under a predetermined tension having one end thereof fixedly secured to said cam ring and the other end hinged on said connecting means, and a second tension member trained over a sprocket roheel mounted on said revolving arm at free end thereof and having one end adjustably secured to said revolving arm and the other end hinged on said connecting rod, so as to exert a turning moment on said connecting means in a direction oppositely to that caused by said first tension member.

Now, one preferable embodiment of the hot board-plate handling device according to the present invention will be described in detail hereinafter by Way of an example with reference to accompanying drawings in which:

FIG. 1 is a plan view showing the essential portion of one preferable embodiment of the board-handling device according to the present invention,

FIG. 2 is a front view showing the same, and

FIG. 3 is a prespective view showing the essential portion shown in FIG. 1 and illustrating the manner in which the board-handling device is driven.

Referring to drawings, FIG. 1 to 3, a vertical shaft 1 is located in the outside of the upright P of the hot plate press on one side at the end where the hot plate A is loaded therein, and has one end fitted into a sprocket wheel 2 and the other end supported by a bracket (not shown). A supporting arm 3 is fixedly mounted on the upright P of the hot press at the loading end thereof so as to support the rotating shaft 1 and is provided with a collar 4 secured thereto and adapted to facilitate the rotation of the shaft 1 therein, as shown in FIG. 3. A rotating arm 5 is fixedly fitted over the rotating shaft 1 at one end and rendered to rotate together with the latter by means of a suitable securing means such as a key.

A cam ring 6 is secured in concentric relationship to the collar 4. A connecting rod 8 is hinged on the rotating arm 5 at the free end of the latter by means of a pin 9. A second sprocket wheel 10 is rotatably fitted over the pin 9. A chain 11 is trained over the sprocket wheel 10 with its links meshed with the latter and adapted to have one end hinged on the connecting rod 8 by means of pin 17 and the other end secured onto the rotating arm 5 through a spring means 12. Another chain 7 is trained over a cam ring 6 and has one end secured to the same and the other end hinged on the connecting rod 8 by means of a pin 14 with a suitable length adjusting means 13, such as a turnbuckle, inserted therein. A pusher rod 15 is connected to the connecting rod 8 at one end thereof and made adjustable in terms of its length by means of a nut 16 threaded thereon at the end.

A third chain 18 is trained over the sprocket wheel 2 so as to drive the shaft 1 as shown in FIG. 3. A pneumatic actuating cylinder 19, which is fixedly mounted on the structure of the press as shown in FIG. 2, is inserted into the chain 18 having both ends of the piston rod 3 connected to the links of the chain. Fluid inlets 19 and 19" are provided at each end of the cylinder, respectively. As shown in FIG. 3, two running portions 18 and 18 of the chain 18 are crossed to each other for the reason to be described hereinbelow.

Now, the operation of the board-handling device according to the present invention will be described hereunder. In order to extract each hot pressed board A on each stage out of the hot press at a time upon completion of the hot pressing process, the pneumatic cylinder 19 is first actuated by supplying working fluid thereto through a suitable inlet such as a fluid inlet 19 so as to rotate the sprocket wheel 2 thereby turning the rotating arm 5 counterclockwise as shown by an arrowhead in FIG. 1. Then, since the chain 7 is hinged on the pin 14 at one end and the cam ring 6 is fixedly secured on the supporting arm 3, that is, on the stationary structure of the hot press, the pin 14 will delineate an involute curve while moving, if the cam ring 6 is an annular wheel, that is, a sprocket wheel. And, if the configuration of the cam ring 6 is modified, it will inevitably entail a change of configuration of the involute curve delineated by the pin 14. By manipulating the length adjusting means 13, the length of the chain 7 can be regulated thereby causing the locus of the pin 14, hence, that of the outer end of the pusher rod 15 to be varied. The pusher rod 15 is urged by the chain 11 and the spring 12 at all times in a direction opposite to that urged by the chain 7 thereby being maintained in'a stable condition.

Hence, when the rotating shaft 1 is driven by the sprocket wheel 2, the pusher rod 15 will be pivoted about the pin 9 and then moved along substantially a straight line so as to displace the boards by means of a link mechanism comprising link members consisting of the rotating arm 5 and the connecting rod 8 and pin members including the pin 14 and 9.

As the pneumatic cylinder 19 is actuated in the opposite direction by supplying the working fluid through the inlet 19", the sprocket wheel 2 will be rotated in a reverse direction thereby bringing the pusher rod 15 back to the original position.

Since two running portions 18' and 18 of the chain 18 are crossed to each other as mentioned hereinabove, two devices shown on each side of FIGS. 1, 3 will operate in an identical manner, that is, two pusher rods 15 and 15A will swing symmetrically to each other with reference to the centre line of the hot plate press.

Although two devices are shown to be located symmetrically on both sides of the press, so as to operate in unison, in the drawings, it will be appreciated that both devices may be adapted to be operated alternately or a single device located only on one side of the press may be made to operate satisfactorily by providing a suitable contact member on the tip of the pusher rod 15 to evenly distribute the pressure on each hot plate or pressed board.

In case of starting the board-handling device according to the present invention so as to displace the hot plate, the other end of the pusher rod 15 will delineate an involute as mentioned here'inabove. However, the arrangement is preferably made so that the radius of curvature of the involute be minimum in the beginning, increased gradually, and then the outer end of the pusher rod 15 will be moved along a straight line (that is, a curve having an radius of infinite value) after having been brought into contact with the 'hot plate. For this purpose, it will be necessary to select the locus of each pin 9 and 14 in a proper way. In other words, in the board-handling device according to the present invention, the pin 9 is caused to move along a circle having a centre concentric with the shaft 1 and the pin 14 along the involute and the involute" is initially located within the circle delineated by the pin 9 and gradually increased in terms of the radius of curvature until it will interesect with the circle, and further increased thereafter. The greater is a difference of the distance between the shaft 1 and the pin 9 from that between the shaft 1 and the pin 14, the more inwardly is urged the pin 14, and hence the less is the radius of curvature of the involute delineated by the outer end of the pusher rod 15. After two loci delineated by the pins 9 and 14 come to interesect with each other and the locus delineated by the pin 14 comes outside of that delineated by the pin 9, the latter will be maintained inside While the former outside. By utilizing this attribute, it is possible to make the outer end of the pusher rod 15 to move along substantially a straight line for the extent required to displace the hot plate although restricted to a certain value by selecting the contour of the cam ring so that the locus delineated by the outer end of the pusher rod will become close to a straight line.

As described in detail hereinabove, the hot plate handling device according to the present invention will minimize the space in which the pusher rod swings and hence the area occupied by the hot plate transferring mechanism of the hot press by action of the link mechanism and permit the hot pressed boards to be accurately displaced out of the hot press or permit the material being hotpressed to be located exactly in a predetermined position on the hot press plate, by simply adjusting the locus delineated by the outer end of the pusher rod as desired.

What is claimed is:

1. A board handling device for a multistage hot plate press, comprising at least one rotating shaft located on one side of said hot plate press at the loading end thereof, means for securing said shaft to the press, a revolving arm fixedly mounted on said shaft and rotatable therewith, a pusher rod, connecting means pivotally mounted on said revolving arm for connecting said pusher rod to said revolving arm, a cam means mounted on said shaft, a first tension member, such as a chain, trained over said cam means and having one end thereof fixedly secured to said cam means and the other end secured to said connecting means, a guide means pivotally mounted on said revolving arm adjacent the end thereof, a second tension member, such as a chain, trained over said guide means and having one end thereof secured to said revolving arm and the other end thereof secured to said connecting means, means for rotating said shaft so as to exert a turning moment on said connecting means by said arm in a direction opposite to that caused by said first tension member.

2. A device according to claim 1, comprising a pin secured on said revolving arm adjacent the end thereof, said guide means being rotatably mounted on said pin, said second tension member being pivoted to said connecting rod, a spring means interposed between said tension member and said revolving arm biassing said connecting rod in one direction to counter-balance the bias exerted onto said connecting means by said first tension member.

3. A board handling device according to claim 1, comprising a second pin secured to said connecting means, said first tension member being pivoted to said second pin adapted to delineate an involute curve as said revolving arm rotates about said shaft.

4. A board handling device according to claim 3, comprising a length adjusting means, such as a turnbuckle, inserted into said first tension member so as to enable the length thereof to be adjusted to change the radius of curvature of the involute curve.

5. A board handling device according to claim 3, wherein the length of said first tension member and said second tension member are selected whereby one part of the involute curve is within a circle delineated by said pin, a second part of said involute curve intersects said circle, while a further part of said involute curve is outside said circle.

6. A board handling device according to claim 1, comprising a toothed wheel secured on said shaft and rotatable therewith, said rotating means exerting a turning moment onto said toothed wheel.

7. A board handling device according to claim 1, wherein said first and second tension member are in the form of chains and wherein said cam means and said guide means are in the form of sprocket wheels.

8. A multistage hot plate press including two board handling devices in side by side relationship, each board handling device comprising a rotating shaft located on one side of said hot plate press at the loading end thereof, means for securing said shaft to the press, a revolving arm fixedly mounted on said shaft and rotatable therewith, a pusher rod, connecting means pivotally mounted on said revolving arm for connecting said pusher rod to said revolving arm, a cam means mounted on said shaft, a first tension member, such as a chain, trained over said cam means and having one end thereof fixedly secured to said cam means and the other end secured to said connecting means, a guide means pivotally mounted on said revolving arm adjacent the end thereof, a second tension member, such as a chain, trained over said guide means and having one end thereof secured to said revolving arm and the other end thereof secured to said connecting means, means for rotating said shafts so as to exert a turning moment on said connecting means by said arms in a direction opposite to that caused by said first tension members.

9. A multistage hot plate press according to claim 8, comprising a pin secured on said revolving arm adjacent the end thereof, said guide means being rotata'bly mounted on said pin, said second tension member being pivoted to said connecting rod, a spring means interposed between said tension member and said revolving arm biassing said connecting rod in one direction to counterbalance the bias exerted onto said connecting means by said first tension member.

10. A multistage hot plate press according to claim 9, comprising a second pin secured to said connecting means, said first tension member being pivoted to said second pin adapted to delineate an involute curve as said revolving arm rotates about said shaft.

References Cited UNITED STATES PATENTS 3,339,757 9/1967 Nagaoka 2l4-16.6

GERALD M. F ORLENZA, Primary Examiner. RAYMOND B. JOHNSON, Assistant Examiner.

US. Cl. X.R 198-221 

